1. Field
Exemplary embodiments of the present invention relate to a nonvolatile memory device and a method for fabricating the same, and more particularly, to a three-dimensional (3-D) structured nonvolatile memory device in which a plurality of memory cells are stacked in a substantially perpendicular direction over a substrate and a method for fabricating the same.
2. Description of the Related Art
A nonvolatile memory device retains stored data although the supply of power is blocked. A variety of nonvolatile memory devices, such as flash memory, are being widely used.
As the improvement of the degree of integration of two-dimensional (2-D) structured nonvolatile memory devices has reached the limit, there has been proposed a 3-D structured nonvolatile memory device in which a plurality of memory cells is formed along channel layers in a substantially perpendicular direction over a semiconductor substrate. More particularly, the 3-D structured nonvolatile memory device is mainly divided into a structure having a straight-line type channel layer and a structure having a U-shaped channel layer.
A process of fabricating the structure having a straight-line type channel layer is relatively simple and easy, but the structure having a straight-line type channel layer may create some concerns in that source resistance is increased when forming a source line by implanting impurities into a silicon substrate. Accordingly, it is necessary to develop a structure capable of solving above concerns.